Dual wheel assembly



Oct. 10, 1950 c. s. ASH 7 2,525,512

DUAL WHEEL ASSEMBLY Filed NOV. 9, 1945 3 Sheets-Sheet l l2 INVENTOR w CHARLES S. ASH

HTTORNEY Oct. 10, 1950 c. s. ASH 2,525,512

DUAL WHEEL ASSEMBLY Filed Nov. 9. 1945 s Sheets-Sheet z 4 INVENTOR CHARLES s. ASH

BY M'M 4 ATTORNEY Oct. 10, 1950 c, s, ASH 2,525,512

DUAL WHEEL ASSEMBLY Filed.Nov. 9. 1945 3 Sheets-Sheet 3 CHARLES S. ASH

HTTORNEY Patentecl Cd. 10, 1950 DUAL WHEEL ASSEMBLY Charles s. Ash, Milford, Mich. Application November 9, 1945, Serial No. 627,637

9 Claims.

The present invention relates to dual wheel assemblies and more particularly to such assemblies in which the individual wheels of the assembly are independently rotatable.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or ma be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations, and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a parthereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:

Fig. l is an axial cross-sectional view of a' typical and illustrative embodiment of the present invention;

Fig. 2 is a transverse cross-sectional view taken along line 22 of Fig. 1; I

Fig. 3 is a cross-sectional view taken along line 33 of Fig. 2; and

Fig. 4. is an axial cross-sectional view, above the centerline of the assembly, of a modified embodi ment of the present invention.

It is an object of the present invention to provide an improved dual wheel assembly in which the individual wheels of the assembly are independently relatively rotatable. The invention provides a wheel assembly of the type just mentioned which is relatively simple in construction and operation, economical to fabricate and maintain, and sufficiently strong for the heaviest types of use. A further object of the invention is the provision of an independently rotatable dual wheel assembly having improved positive braking means operable to brake each wheel of the assembly. The invention further provides braking means for a differential dual wheel assembly which exert a powerful equalized braking effort on each wheel of the assembly when applied.

In an illustrative embodiment of the present invention, which is herein shown and described by wa of example, there is provided on a trailing type axle end a freely rotatably mounted inner wheel having a hub portion upon which an outer wheel is mounted for rotation independently of the inner wheel] The braking means for the wheel assembly include a brake drum secured to theinner. wheel for exerting a braking effort thereon and means for automatically positively locking the inner and outer wheel together when braking friction is operable upon said drum. The positive locking means between the inner and outer wheels comprise a ring gear secured to the outer wheel engaging pinion gears on the inner wheel, and interengageable elements on the movably mounted brake drum and pinion gear shafts which engage upon application of the brake and prevent rotation of the pinion gears. A modified embodiment-of the invention herein shown and described provides for mounting the wheels of the assembly individually upon the axle end with their own anti-friction bearings, and braking means similar to those just discussed are provided for the wheels.

It will be understood that the foregoing general description and the following detailed description as well are exemplary and explanatory of the invention but are not restrictive thereof;

Referring now in detail to the embodiments of the present invention shown in the accompanying drawings, and referring first to the embodiment of Figs. 1 to 3 inclusive, the differential dual wheel assembly is shown as mounted on the trailing type axle end In which may be of a standard type. The inner wheel of the assembly indicated generally b the numeral II comprises an axially inner tubular hub portion I2 which serves as the hub for the inner wheel and an axially extending outer hub portion 13 integral with portion i2 upon which the outer wheel of the assembly is journalled for rotation. As shown, an anti-friction bearing I4 is seated at the inner end of hub portion l2 and a second anti-friction bearing 15 is seated at the inner end of the outer extension or hub portion [3, thus stably mounting the wheel assembly on axle end ii! and providing for the free rotation of the integral hub portion 2!. As shown, portion 2| joins web portion' in an inclined or dished web portion I9. At its outer periphery portion 2| is provided with inclined surfaces 22 upon which a conventional tire rim 23 may be demountably mounted by means of lugs 24, lug bolts 25 and nuts 26.

The outer wheel of the dual wheel assembly is 55 indicated generally by the numeral in the drawings and comprises a tubular hub portion 3|, an inwardl dished web portion 32 integral with portion 3| and connected thereto at a central part of its length, and a web portion 33 extending radially outwardly from the periphery of web portion 32. A tire rim 34, which is preferably a duplicate of inner rim 23 but oppositely disposed in the assembly, is mounted on axially extending shoulder 35 at the periphery of web portion 33 against a removable ring 33 seated in a groove in the shoulder 35, and lugs 31, lug bolts 38, and nuts 39 complete the demountable mounting of the rim on the outer wheel.

The outer wheel hub 3| is mounted on a pair of external cylindrical seats 40 and 4| of the hub portion l3 of the inner wheel II and bushings 42 and 43 are interposed between the hub members. Outer wheel 30 is thus mounted to rotate on hub portion l3 independently of the inner wheel II when the two wheels of the assembly are following paths of unequal lengths as, for instance, when the vehicle is turning a corner. A retaining cap 44 is secured to the outer end of hub portion |3 by means of tap bolts 45 and a thrust washer 46 is provided 'be tween the cap and hub 3| as a thrust bearing for the outer wheel. Cap 44 is provided with an integral cylindrical peripheral portion 41 overlapping the end of hub 3|, and an interposed sealing ring 48 seals the inter-hub bushing assembly. At the inner end of hub 3| there is positioned a ring gear '50 which is secured to the hub by a plurality of tap bolts for purposes hereinafter set forth, and between the axially inner surface of the gear member and web of the inner wheel N there is provided a second thrust washer 52 to complete the thrust bearing assembly between hub 3| and the inner wheel hub member |2--| 3.

The braking means for the dual wheels II and comprise means for braking the inner wheel I and automatically and simultaneously locking the wheels together so thata powerful and balanced braking effect is realized in the wheel assembly. As illustratively shown in the drawings, these means comprise a brake drum 5.5 at the inner side of the inner wheel to be frictionally engaged by brake shoe 56 which may be anchored and actuated in any suitable and known manner. Drum 55 is mounted for limited rotary movement with respect to the inner wheel H by means of a clutch member 51 which is secured to the brake drum mounting flange 58 by means of a plurality of bolts 59 and nuts 6|], as shown in Fig. 3 of the drawings. Clutch member 5! is provided at its inner periphery with an integral axially extending cylindrical base 6| which is journalled on a finished outersurface at the end of hub portion I2 and a cylindrical bushing-62 is preferably provided between the partsv As best shown in Fig. 2, clutch member 5] is interrupted at diametrically opposed portions of its circumference radially outwardly of base 6|, and these interrupted places accommodate pinion gears 65 which have relatively coarseand deep teeth. Pinion gears 65 are mounted on shafts 66 for correlative rotation therewith and with other pinion gears 61 secured to the opposite ends of shafts 66. These latter pinion gears, 61, are in mesh with ring gear 50' which, as has been explained, is secured to the hub 3|. of the outer wheel of the assembly. The pinion gear shafts 66 are journalled in heavy, cylindrical portions 68 which are formed. as integral;

4 parts of the inner wheel II, and the axially inner ends of the shafts are journalled in annular plate 69 which is secured to the inner end of hub portion |2 by means of tap bolts I0. Plate 69 also erves as a thrust member for base 6| of clutch member 51.

As shown in Figs. 2 and 3, single toothed members 12 are fitted over the exposed walls of clutch member 51 at the interrupted places wherein pinions 65 are positioned, and the clutch and toothed members are securely joined by means of rivets I3. It will be apparent from the construction described that the inner and outer wheels of the assembly are normally capable of independent relative rotation but, upon application of the brake, drum 55 will first rotate somewhat with respect to the inner wheel upon base portion 6| of clutch member 51 until single toothed members 12 have engaged the teeth of pinions 65. Braking effort is thereupon exerted directly upon the inner wheel of the assembly, and likewise rotation of pinion 6'! is. prevented. The inner and outer wheels of the assembly are therefore locked together for correlative rotation through ring gear 50 and pin-- ions 61, and the braking effort exerted upon the inner wheel is likewise exerted upon the outer one. It will be apparent from the drawings that the braking effort is the same for either direction in which the vehicle may be travelling, as single toothed members 12 are provided at either side of pinions 65 on clutch member 51.

Means are provided for maintaining the drum 55, clutch member 51 and single toothed member '12 in a central and disengaged position when the brake is off. As embodied, the bolts 59 are integrally formed with cylindrical portions [5. which are bored to accommodate plungers 15, Caps 11 are provided over an end of the bored members 15 and coiled springs 11' urge the plungers against flat headed screws 18 extending from either side of cylindrical journals 68. It may be seen that the spring pressed plungers will keep the drum 55 and its associated mechanism in a central positionuntil the brake shoe is engaged with it, and also will prevent chattering of the brake mechanism.

The embodiment of the invention shown in Fig. 4 of the drawings comprises an inner wheel with hub portion 8| mounted upon axle end 82 by means of roller bearings 83 and 84, and an outer wheel 85 mounted for rotation independently of the inner wheel upon axle end ;82 by means of its individual roller bearings 86 and 87. The bearing and hub assembly are maintained in position by washer 88 and nut 89 on the axle end.

The braking means for the embodiment of the invention of Fig. 4 are entirely similar to those just described for the embodiment shown in Figs. lto 3 inclusive, comprising a ring gear -90 secured to the outer wheel hub for rotation there-- with meshing with a pinion gear 9|. These gears are carried by shafts 92 journalled in thickened portions 93 of inner wheel 80, and at their axially inner ends shafts 92 carry otherpinions 94 to be engaged by tooth members (not shown) which are fixed with respect to brake drum 95. The brake drum 95 is mounted by means of a clutching member similar to member 51 in the first embodiment and having'za cylindrical base portion 96 for limited rotary motion on hub 8|. As described for the'first embodiment, application of the brake rotates drum 95 somewhat to apply a braking effort to inner wheel 80 through pinion 94 and, by preventing rotation of pinion 9i, locks wheels 80 and 85 together for balanced and simultaneous braking action.

The invention in its broader aspects is not limited to the specific mechanisms shown and de scribed but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the in vention and Without sacrificing its chief advantages.

What I claim is:

1. A dual wheel assembly comprising, in combination, a pair of side by side, independently rotatable wheels, a brake element mounted for limited relative rotation with respect to one wheel to be rotationally retarded with respect thereto when the brakes are applied, and means for locking said brake element with respect to said one wheel preventing relative rotation and for locking said one wheel and the other wheel. together preventing relative rotation upon re tarding and rotating said element, said means including a pair of interconnected pinion gears on said one wheel one of said gears being normally disengaged from but engageable by said element upon rotation thereof and a ring gear secured to said other wheel meshing with the other pinion gear.

2. A dual wheel assembly comprising, in combination, a pair of side by side, independently rotatable wheels, a brake element mounted for limited relative rotation with respect to one wheel to be rotationally retarded with respect thereto when the brakes are applied, and means for locking said brake element with respect to said one wheel preventing relative rotation and for simultaneously and automatically locking said one wheel and the other wheel together preventing relative rotation upon retarding and rotating said element, said means including a pair of pinion gears mounted for correlative rotation on a shaft journalled in said one wheel one of said gears being normally disengaged from but engageable by said element upon rotation thereof and a ring gear secured to said other wheel meshing with the other pinion gear.

3. A dual wheel assembly comprising, in combination, a pair of side by side, independently rotatable wheels, means for retarding rotation of one of said wheels upon application of the brake including a brake element relatively movable from unlocked position into locked engagement with said one wheel, and means for locking said wheels together for correlative rotation upon application of the brake including a pinion gear on said one wheel meshing with a ring gear on the other wheel and means for preventing rotation of said pinion gear upon movement of said element into locked engagement with said one Wheel.

4. A dual wheel assembly comprising, in combination, a pair of side by side, independently rotatable wheels, a pair of pinion gears mounted for correlative rotation on a shaft journalled in one of said Wheels, a ring gear secured to the other of said Wheels meshing with one of said pinion gears, a brake element yieldably held with respect to said one of said wheels, and toothed means on said element normally disengaged to engage the other of said pinion gears upon application of the brakes.

5. A dual wheel assembly comprising, in combination, a pair of side by side, independently rotatable wheels, a pair of pinion gears mounted for correlative rotation on a shaft journalled in one of said wheels, a ring gear secured to the other of said wheels meshing with one of said pinion gears, a brake drum, means interconnecting the drum and said one of said wheels for normally correlative rotation permitting relative rotation upon frictional retarding of said drum, and toothed means on the drum engageable with the other of said pinion gears upon relative rotation of the drum and said one wheel.

6. A dual wheel assembly comprising, in combination, a pair of side by side, independently rotatable wheels, a pair of pinion gears mounted for correlative rotation on a shaft journalled in the inner wheel, a ring gear secured to the inner side of the outer wheel meshing with one of said inion gears, a brake drum at the inner side of the inner wheel journalled thereon and having toothed members engageable with the other of said pinion gears, and resilient means between the brake drum and the inner wheel normally holding said toothed means out of engagement with said other pinion gear but permitting engagement upon frictionally retarding rotation of said brake drum.

'7. A dual wheel assembly comprising, in combination, an inner wheel having a hub mounted for rotation upon an axle end, an outer wheel having a hub journalled on the hub of the inner wheel, a ring gear on the outer wheel, a pair of pinion gears mounted for correlative rotation on the inner wheel one of said gears meshing with said ring gear, and a brake element journalled on the inner wheel having toothed means normally disengaged for engaging the other of said pinion gears upon rotational retarding of the element.

8. A dual wheel assembly comprising, in combination, an inner wheel having a hub journalled on an axle end and an outer wheel having a hub journalled on the axle end beside the inner wheel hub, a ring gear on the outer wheel hub, a pair of pinion gears mounted for correlative rotation on a shaft journalled in the inner wheel one of said pinions meshing with said ring gear, and a brake element journalled on the hub of the inner wheel having toothed means normally disengaged for engaging the other of said pinion gears upon rotational retarding of the element.

9. A dual wheel assembly comprising, in combination, a pair of wheels mounted for independent relative rotation upon an axle end, a ring gear on one of said wheels and a pinion gear meshing therewith on the other of said wheels, and braking means including a braking element engageable with the inner wheel upon application of the brake and means between the element and the pinion gear normally disengaged and engageable for preventing rotation thereof upon application of the brake.

CHARLES S. ASH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,132,029 Higbee Oct. 4, 1938 2,192,023 Ash Feb. 27, 1940 2,214,457 Fuhrman Sept. 10, 1940 2,260,828 Burger Oct. 28, 194.1 

